The invention relates to a method for testing a brake and return mechanism of an artillery barrel whereby a backward thrust is applied to the muzzle of a barrel and the behaviour of the brake and return mechanism is recorded.
In the known art, the backward thrust is applied to the muzzle by means of a ram, which is fired against the muzzle when the powder in the powder chamber explodes. Such a powder chamber is only suitable for a determined powder charge so that a particular apparatus used is only suitable for testing brake and return mechanisms of one determined dimension. The use of powder is dangerous and the noise it causes is a nuisance. The impulse of the test thrust applied cannot be reproduced accurately.
The invention has for its object to provide an improved method whereby varying brake and return mechanisms can be tested with one and the same apparatus, resulting in considerably less noise and danger than is caused in the case of powder explosions and /or in it being possible to carry out the test more accurately. To achieve this with the method according to the invention, the thrust on the muzzle is applied by means of at least one pretensioned gas cylinder being released.
If the gas cylinder is released by destruction of attachment means, said gas cylinder is freed in a simple manner.
An object of the invention is to provide a method of testing the recoil and return mechanism of ordnance pieces by subjecting same to an energy impulse applied to the muzzle of the barrel of the piece or of a dummy barrel in which the energy impulse is the kinetic energy of a mass initially transferred resiliently to the barrel. The kinetic energy transfer causes the barrel or dummy to be subjected to forces varying with time which approximate the time history of forces which would be applied to the piece if it were actually being fired. The force/time diagram caused by the energy transfer is recorded as a record of the test.
In regard to the above objective, it is of paramount concern that the time history of forces acting upon the piece during actual firing thereof be approximated during the test. This time history is approximated by (1) assuring that the kinetic energy imparted to the mass is accurately of a predetermined value and (2) that the kinetic energy transfer to the piece is initially cushioned in controlled fashion to produce a force which increases with time to a peak value and thereafter, subsequent to such cushioning, decreases with time to zero. Stated otherwise, the kinetic energy transfer may be thought of as occurring in two stages of mass deceleration, the first stage being relatively gradual and the second stage being relatively abrupt. The transition between stages is marked by the cessation of the cushioned transfer and the onset of full impact transfer.
Another object of the invention is to provide a method in which the kinetic energy imparted to the mass is closely controlled. To this end, the mass impelling plunger is "loaded" with a predetermined gas pressure, the plunger is locked in position while this gas pressure prevails, and the plunger is then released from this position by destruction of a restraining member. In this way, the prevailing pressure of the gas is closely controlled so that the mass is impelled to a predetermined velocity and thus, because its weight is also controlled, has a predetermined kinetic energy before its kinetic energy is transferred to the ordnance piece.
Another object of the invention is the provision of apparatus for carrying out the method of this invention.
Other and different objects of the invention will become apparaent as the following description proceeds.